The present invention relates to a treating device for treating the video head and/or rotating drum of a video recorder and/or playback unit, and in particular, though not limited to a treating device for cleaning the video head and/or rotating drum. The invention also relates to a method for treating a video head and/or drum of a video recorder and/or playback unit.
Treating devices for treating a video head and/or drum of a video recorder and/or playback unit are known. Typically, such treating devices are provided for cleaning the video head and/or drum. In general, they comprise a cassette housing which is substantially identical to a video cassette housing of the type which houses a video magnetic tape. A cleaning brush typically is carried on a carrier arm which is pivotally mounted within the cassette housing and is pivotal from a retracted position within the housing to a cleaning position with the cleaning brush in engagement with the drum.
One such cleaning device is disclosed in European Patent Specification No. 0,210,787. The cleaning device disclosed in this European specification comprises a cassette housing. A carrier arm which is located within the housing carries a cleaning brush for cleaning the video head and drum. A cleaning tape is wound onto a pair of spools in the housing in substantially similar fashion as a magnetic tape is wound onto the corresponding spools in a video tape cassette. The cleaning tape has a number of functions, one of which is to clean the video head and drum as well as other components such as the sound and erase heads in the normal tape path through a video recorder and/or playback unit. Another function of the cleaning tape is to urge the cleaning brush into cleaning engagement with the video head and drum.
Another cleaning device for cleaning a video head and/or drum of a video recorder and/or playback unit is disclosed in European Patent Specification No. 0,439,375. The cleaning device of this European specification also comprises a cassette housing which is substantially similar to a video tape cassette housing. In this cleaning device cleaning of the video head and drum is exclusively carried out by a cleaning brush which is carried on a carrier arm. A drive mechanism is provided in the cassette housing for urging the carrier arm from a retracted position with the carrier arm and the cleaning brush located within the cassette housing and a cleaning position with the cleaning brush in cleaning engagement with the video head and drum. A timing mechanism is also provided within the cassette housing for controlling the drive mechanism for preventing the drive mechanism urging the carrier arm and cleaning brush from the retracted to the cleaning position, until tape withdrawal rollers for withdrawing a magnetic tape from a video tape cassette into engagement with the drum have moved from the cassette receiving area for avoiding any danger of the carrier arm and/or cleaning brush becoming entangled with the rollers. The timing mechanism also ensures that the carrier arm and the cleaning brush are urged from the cleaning position to the retracted position in advance of the tape withdrawing rollers returning to the cassette receiving area, similarly for preventing entanglement of the carrier arm and brush with the tape withdrawal rollers.
In the cleaning device disclosed in European specification No. 0,210,787, the fact that the cleaning tape is adapted for urging the carrier arm and the cleaning brush from the retracted position to the cleaning position under the action of the tape withdrawal rollers avoids the danger of the cleaning brush and carrier arm becoming entangled with the tape withdrawal rollers.
It is essential that the parts of a cleaning device for cleaning a video head and/or a drum of a video recorder and/or playback unit should not become entangled with the tape withdrawal rollers. Such tape withdrawal rollers are mounted on carrier arms, and the carrier arms are driven by a drive mechanism for urging the tape withdrawal rollers for urging the magnetic tape from the video tape cassette into engagement with the drum. The drive mechanism and indeed the carrier arms which carry the tape withdrawal rollers are highly precision engineered, and in general, are relatively delicate components. Thus, if subjected to any undue resistance to their movement either for withdrawing or returning a magnetic tape from or to a video tape cassette, the tape withdrawal rollers could easily be put out of adjustment. Indeed, if the resistance to their movement is excessive the carrier arms and drive mechanism could be damaged. Accordingly, it is essential that there should be no danger of any part of a cleaning device, and in particular, a cleaning brush or other treating means, and its associated carrier arm becoming entangled with the tape withdrawal rollers.
The cleaning devices disclosed in European specifications Nos. 0,210,787 and 0,439,375 achieve this objective. However, in the cleaning device of European Specification No. 0,439,375 the timing mechanism is required in order to control the drive means which urges the carrier arm and in turn the cleaning brush into the cleaning position. Such timing mechanisms tend to be relatively expensive. The objective of avoiding entanglement of the cleaning brush and carrier arm with the tape withdrawal rollers is achieved in the cleaning device of European Patent Specification No. 0,210,787 by virtue of the fact that the cleaning brush and carrier arm are moved into the cleaning position by the cleaning tape, which itself is urged by the tape withdrawal rollers. However, in certain cases it is desirable to provide a cleaning device, and indeed, a treating device for treating a video head and/or drum of a video recorder and/or playback unit which does not include a cleaning tape, and in which entanglement of the cleaning brush or other treating means and the carrier arm with the tape withdrawal rollers and other moveable components within a video recorder and/or playback unit is avoided, and which does not require the provision of a timing mechanism.
The present invention is directed towards providing such a treating device for treating the video head and/or rotating drum of a video recorder and/or playback unit.
According to the invention there is provided a treating device for treating the video head and/or rotating drum of a video recorder and/or playback unit, the device comprising a locating means for locating the device in a cassette receiving area of the video recorder and/or playback unit, a carrier means for carrying a treating means for treating the head and/or drum, the carrier means being mounted on the locating means and being moveable between a retracted position within the cassette receiving area when the device is located therein and a treating position with the treating means in treating association with the head and/or drum, wherein the retaining means is provided for retaining the carrier means in the retracted position, the retaining means being responsive to the locating means being entered into the cassette receiving area for releasing the carrier means from the retracted position, and an abutment means is provided associated with the carrier means for co-operating with a component in the cassette receiving area in the video unit for retaining the carrier means in the retracted position while the component is in the cassette receiving area, the abutment means being responsive to movement of the component from the cassette receiving area for permitting movement of the carrier means into the treating position.
Preferably, the retaining means is adapted for retaining the carrier means in the retracted position while the locating means is being entered into the cassette receiving area until the abutment means is aligned with the component in the cassette receiving area for engagement thereof.
Advantageously, the retaining means is responsive to the locating means progressively being entered into the cassette receiving area for progressively releasing the carrier means from the retracted position.
In one embodiment of the invention the component in the cassette receiving area with which the abutment means is engageable is a tape withdrawal roller for withdrawing a magnetic tape of a video cassette from the video cassette into engagement with the rotating drum.
In another embodiment of the invention an urging means is provided for urging the carrier means from the retracted position to the treating position. Preferably, the retaining means acts against the urging means for retaining the carrier means in the retracted position.
In one embodiment of the invention the urging means comprises a resilient urging means. Preferably, the resilient urging means comprises a torsion spring.
In one embodiment of the invention the carrier means comprises an elongated carrier arm. Preferably, the carrier arm is pivotally mounted on the locating means, and is pivotal between the retracted and the treating positions. Advantageously, the carrier arm extends between a pivot mounting means for pivotally mounting the carrier arm on the locating means and a connecting means spaced apart from the pivot mounting means for connecting the treating means to the carrier arm.
In one embodiment of the invention the abutment means is located on the carrier arm.
In another embodiment of the invention the abutment means is located on the carrier arm intermediate the pivot mounting means and the connecting means. Preferably, the abutment means is spaced apart from both the pivot mounting means and the connecting means. Advantageously, the abutment means is an elongated abutment means extending along the carrier arm.
In one embodiment of the invention the abutment means is formed by a side edge of the carrier arm.
In another embodiment of the invention a treating means is mounted on the connecting means of the carrier arm. Preferably, the treating means is pivotally mounted on the connecting means. Advantageously, a support means is pivotally connected to the connecting means of the carrier arm for pivotally carrying the treating means.
In one embodiment of the invention the treating means is a cleaning means. Advantageously, the treating means comprises a cleaning brush. Preferably, the cleaning brush comprises a support base and a plurality of cleaning fibres extending from the support base, the support base being engageable with the support means. Advantageously, the support base of the cleaning means is releasably engageable with the support means.
In one embodiment of the invention the retaining means is pivotally connected to the locating means, and is pivotal between a retaining position for retaining the carrier means in the retracted position and a release position for releasing the carrier means from the retracted position.
In another embodiment of the invention the abutment means is located adjacent the locating means for engaging the component in the cassette receiving area as the device is being entered into the cassette receiving area.
In a further embodiment of the invention the locating means comprises a base member defining the cassette receiving area of the video recorder and/or playback unit for locating the treating device in the receiving area.
In another embodiment of the invention the locating means comprises a housing of which the base member forms a part, the housing defining a hollow interior region for accommodating the carrier means and the treating means. Preferably, the housing is of size and shape substantially similar to a video cassette housing of a magnetic video tape cassette. Advantageously, the base member of the housing forms a base wall thereof, and a top wall is provided spaced apart above the base wall, the base and top walls terminating in front edges which in use face towards the drum, the front edges of the respective top and base walls defining a forward plane within which a forward opening is provided to the hollow interior region. Preferably, the carrier means is pivotal from the retracted position with the treating means located within the housing internally of the forward plane to the treating position with the treating means externally through the forward opening and externally of the forward plane.
In one embodiment of the invention a lid is pivotally connected to the housing for closing the forward opening, the lid being pivotal from an open position exposing the forward opening to a closed position with the forward opening closed. Advantageously, the retaining means is mounted on the lid, and is moveable between the retaining position and the release position as the lid is pivoted between the closed position and the open position, respectively. Preferably, when the lid is in the closed position the retaining means extends inwardly into the housing through the forward opening. Advantageously, the lid is pivotal from the closed to the open position in response to the treating device being entered into the cassette receiving area.
In one embodiment of the invention the retaining means is co-operable with the treating means for retaining the carrier means in the retracted position.
In a further embodiment of the invention the abutment means is engageable with the component in the cassette receiving area as the locating means is being lowered into the cassette receiving area.
Further, the invention provides a method for treating a video head and/or rotating drum of a video recorder and/or playback unit using a treating device which comprises a locating means for locating the device in a cassette receiving area of the video recorder and/or playback unit, and a carrier means for carrying a treating means for treating the head and/or drum, the method comprising the steps of placing the locating means in the cassette receiving area of the video recorder and/or playback unit for locating the device in the cassette receiving area, and urging the carrier means into a treating position with the treating means positioned for treating the video head and/or drum, wherein the carrier means is retained in a retracted position in the cassette receiving area until an abutment means associated with the carrier means is aligned with a component in the cassette receiving area, and releasing the carrier means so that the abutment means engages the component for retaining the carrier means in the retracted position until the component commences to move from the cassette receiving area.